As burst error always occurs at the wireless interface, the current WCDMA system has introduced an RLC layer in the protocol layering to meet the bit error rate requirements, and such a layer is mainly used to realize functions of numbering, segmentation, cascading, and retransmission of data. Particularly, taking transmitting an uplink RLC layer data from a user equipment (UE) to a universal terrestrial radio access network (UTRAN) as an example, the RLC layer data sent from the UE-RLC layer is transmitted to an RLC layer of a radio network controller (RNC) (RNC-RLC) through a medium access control (MAC) layer of the UE (UE-MAC), a UE physical layer, and a node B (NB) physical layer of a UTRAN, and an RNC-MAC layer at the UTRAN, then, the RNC-RLC layer feeds back a data-receiving packet to the UE-RLC layer according to the current receiving state, in which the packet generally indicates whether the current data has been received correctly or not, and then the UE-RLC layer determines whether to transmit a subsequent new data or retransmit the current data according to the packet, so as to ensure the retransmission of the data that has not been received correctly to meet the bit error rate requirements.
FIG. 1 is a wireless data transmission method, in which, for example, the UE transmits an uplink RLC layer data packet X to the UTRAN. The wireless data transmission method in the prior art includes the following steps.
Steps 101-107: After receiving a high-level data packet from an upper layer of the RLC layer, a UE-RLC layer module adds RLC relevant control information into the packet and then encapsulates the packet into an RLC layer data packet X, and buffers the data packet X; then, after performing an MAC layer process on the data packet X through a UE-MAC layer module, the UE-RLC layer module transmits the data packet X to a UE physical layer module; then, the UE physical layer module performs a transmitting process on the data containing the data packet X, such as channel encoding, spreading, and modulating; then, the UE physical layer module transmits the data containing the data packet X to an NB physical layer module; then, the NB physical layer module performs a receiving process on the received data containing the data packet X, such as demodulating, despreading, and channel decoding; after performing an MAC layer process on the processed data through an RLC-MAC layer module, the NB physical layer module transmits the data packet X to an RNC-RLC layer module; the RNC-RLC layer module determines whether the data packet X is correctly received or not; if the data packet X is determined to be correctly received, the RNC-RLC layer module decapsulates the data packet X, extracts and then transmits the high-level packet to the upper layer of the RLC layer, and meanwhile generates an RLC layer control packet Y1 indicating that the data is correctly received, and then proceeds to Step 108 and subsequent steps; if the data packet X is determined to be incorrectly received, the RNC-RLC layer module generates an RLC layer control packet Y0 indicating that the data is incorrectly received, and then proceeds to Step 108 and the subsequent steps. In Step 107 of FIG. 1, the data is, for example, incorrectly received.
Steps 108-113: After performing the MAC layer process on the control packet Y1 or Y0 through the RNC-MAC layer module, the RNC-RLC module transmits the control packet Y1 or Y0 to the NB physical layer module; then, the NB physical layer module performs the transmitting process on the control packet Y1 or Y0, and then transmits the control packet Y1 or Y0 to the UE physical layer module; then, the UE physical layer module performs the receiving process on the control packet Y1 or Y0, and then transmits the control packet Y1 or Y0 to the UE-RLC layer module through the UE-MAC layer module; then, the UE-RLC layer module parses the control packet Y1 or Y0, to find out whether the data packet X is correctly transmitted or not. If the UE-RLC layer module receives the control packet Y1 indicating that the data is correctly received by the RNC-RLC layer module, it drops the data packet X and ends up the process. If the UE-RLC layer module receives the control packet Y0 indicating that the data is incorrectly received by the RNC-RLC layer module, it proceeds to Step 114 and subsequent steps. In Steps 108-113 of FIG. 1, the control packet Y0 is taken as an example.
Steps 114-119: The UE-RLC layer module reads the data packet X from the buffer cache and then the data packet X is performed with the MAC layer process through the UE-MAC layer module, and then transmitted to the UE physical layer module; then, the UE physical layer module performs the transmitting process on the data containing the data packet X, and then transmits the data containing the data packet X to the NB physical layer module; then, the NB physical layer module performs the receiving process on the data containing the data packet X, and then transmits the data packet X to the RNC-RLC layer module after performing the MAC layer process on the processed data through the RLC-MAC layer module; then, the RNC-RLC layer module determines whether the data packet X is correctly received or not; if the data packet X is determined to be correctly received, the RNC-RLC layer module decapsulates the data packet X, extracts and then transmits the high-level packet to the upper layer of the RLC layer, and meanwhile generates an RLC layer control packet Y1 indicating that the data is correctly received, and then proceeds to Step 120 and subsequent steps; if the data packet X is determined to be incorrectly received, the RNC-RLC layer module generates an RLC layer control packet Y0 indicating that the data is incorrectly received, and then proceeds to Step 120 and subsequent steps. In Step 119 of FIG. 1, the data is, for example, incorrectly received.
Steps 120-125: After performing the MAC layer process on the control packet Y1 or Y0 through the RNC-MAC layer module, the RNC-RLC module transmits the control packet Y1 or Y0 to the NB physical layer module; then, the NB physical layer module performs the transmitting process on the control packet Y1 or Y0, and then transmits the control packet Y1 or Y0 to the UE physical layer module; then, the UE physical layer module performs the receiving process on the control packet Y1 or Y0, and then transmits the control packet Y1 or Y0 to the UE-RLC layer module through the UE-MAC layer module; then, the UE-RLC layer module parses the control packet Y1 or Y0 to find out whether the data packet X is correctly transmitted or not. If the UE-RLC layer module receives the control packet Y1 indicating that the data is correctly received by the RNC-RLC layer module, it drops the data packet X, and ends up the process. If it receives the control packet Y0 indicating that the data is incorrectly received by the RNC-RLC layer module, it executes Steps 114-125 again, till the UE-RLC layer module receives the control packet Y1 indicating that the data is correctly received by the RNC-RLC layer module. In Steps 120-125 of FIG. 1, the control packet Y1 is taken as an example.
After receiving the control packet Y1 indicating that the data is correctly received by the RNC-RLC layer module, the UE-RLC layer module drops the buffered current data packet, so as to send a subsequent new RLC layer data.
Currently, as for the RLC layer data transmission method adopting the technique in the prior art, the transmitter determines whether to retransmit the current data or to transmit a new data, merely after the data-receiving packet fed back from the RLC layer of the receiver is received. Taking the uplink state in FIG. 1 as an example, the data-receiving packet is generated by the RNC-RLC layer and then transmitted to the UE through the NB physical layer. As the NB physical layer needs to perform corresponding processing on the data, the feed-back speed of the data-receiving packet is extremely slow, and as a result, the data transmission speed over the RLC layer is rather slow.